/*
    This file is part of the iText (R) project.
    Copyright (c) 1998-2022 iText Group NV
    Authors: iText Software.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License version 3
    as published by the Free Software Foundation with the addition of the
    following permission added to Section 15 as permitted in Section 7(a):
    FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
    ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
    OF THIRD PARTY RIGHTS
    
    This program is distributed in the hope that it will be useful, but
    WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    or FITNESS FOR A PARTICULAR PURPOSE.
    See the GNU Affero General Public License for more details.
    You should have received a copy of the GNU Affero General Public License
    along with this program; if not, see http://www.gnu.org/licenses or write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA, 02110-1301 USA, or download the license from the following URL:
    http://itextpdf.com/terms-of-use/
    
    The interactive user interfaces in modified source and object code versions
    of this program must display Appropriate Legal Notices, as required under
    Section 5 of the GNU Affero General Public License.
    
    In accordance with Section 7(b) of the GNU Affero General Public License,
    a covered work must retain the producer line in every PDF that is created
    or manipulated using iText.
    
    You can be released from the requirements of the license by purchasing
    a commercial license. Buying such a license is mandatory as soon as you
    develop commercial activities involving the iText software without
    disclosing the source code of your own applications.
    These activities include: offering paid services to customers as an ASP,
    serving PDFs on the fly in a web application, shipping iText with a closed
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    For more information, please contact iText Software Corp. at this
    address: sales@itextpdf.com
 */
using System;
using System.IO;
using System.Text;
using System.Collections.Generic;
using System.util;
using iTextSharp.text.error_messages;
using iTextSharp.text.io;
using iTextSharp.text.pdf.fonts.cmaps;

namespace iTextSharp.text.pdf {

    /**
     * Creates a CJK font compatible with the fonts in the Adobe Asian font Pack.
     *
     * @author  Paulo Soares
     */

    internal class CJKFont : BaseFont {
        /** The encoding used in the PDF document for CJK fonts
         */
        internal const string CJK_ENCODING = "UNICODEBIGUNMARKED";
        private const int FIRST = 0;
        private const int BRACKET = 1;
        private const int SERIAL = 2;
        private const int V1Y = 880;
            
        internal static Properties cjkFonts = new Properties();
        internal static Properties cjkEncodings = new Properties();
        private static Dictionary<String, Dictionary<String, Object>> allFonts = new Dictionary<string,Dictionary<string,object>>();
        private static bool propertiesLoaded = false;
        
        /** The path to the font resources. */
        public const String RESOURCE_PATH_CMAP = RESOURCE_PATH + "cmaps.";
        private static Dictionary<String,Dictionary<String,object>> registryNames = new Dictionary<string,Dictionary<string,object>>();
        private CMapCidByte cidByte;
        private CMapUniCid uniCid;
        private CMapCidUni cidUni;
        private String uniMap;

        /** The font name */
        private string fontName;
        /** The style modifier */
        private string style = "";
        /** The CMap name associated with this font */
        private string CMap;
        
        private bool cidDirect = false;
        
        private IntHashtable vMetrics;
        private IntHashtable hMetrics;
        private Dictionary<String, Object> fontDesc;
        
        private static void LoadProperties() {
            if (propertiesLoaded)
                return;
            lock (allFonts) {
                if (propertiesLoaded)
                    return;
                try {
                    LoadRegistry();
                    if (registryNames.ContainsKey("fonts"))
                    {
                        foreach (String font in registryNames["fonts"].Keys) {
                            allFonts[font] = ReadFontProperties(font);
                        }
                    }
                }
                catch {
                }
                propertiesLoaded = true;
            }
        }

        private static readonly char[] cspace = {' '};
        private static void LoadRegistry() {
            Properties p = new Properties();
            using (Stream isp = StreamUtil.GetResourceStream(RESOURCE_PATH_CMAP + "cjk_registry.properties")) {
                p.Load(isp);
            }
            foreach (string key in p.Keys) {
                String value = p[key];
                String[] sp = value.Split(cspace, StringSplitOptions.RemoveEmptyEntries);
                Dictionary<String,object> hs = new Dictionary<string,object>();
                foreach (String s in sp) {
                    hs[s] = null;
                }
                registryNames[key] = hs;
            }
        }

        /** Creates a CJK font.
         * @param fontName the name of the font
         * @param enc the encoding of the font
         * @param emb always <CODE>false</CODE>. CJK font and not embedded
         * @throws DocumentException on error
         * @throws IOException on error
         */
        internal CJKFont(string fontName, string enc, bool emb) {
            LoadProperties();
            this.FontType = FONT_TYPE_CJK;
            string nameBase = GetBaseName(fontName);
            if (!IsCJKFont(nameBase, enc))
                throw new DocumentException(MessageLocalization.GetComposedMessage("font.1.with.2.encoding.is.not.a.cjk.font", fontName, enc));
            if (nameBase.Length < fontName.Length) {
                style = fontName.Substring(nameBase.Length);
                fontName = nameBase;
            }
            this.fontName = fontName;
            encoding = CJK_ENCODING;
            vertical = enc.EndsWith("V");
            CMap = enc;
            if (enc.Equals(IDENTITY_H) || enc.Equals(IDENTITY_V))
                cidDirect = true;
            LoadCMaps();
        }

        internal String UniMap {
            get {
                return uniMap;
            }
        }
        
        private void LoadCMaps() {
            try {
                fontDesc = allFonts[fontName];
                hMetrics = (IntHashtable)fontDesc["W"];
                vMetrics = (IntHashtable)fontDesc["W2"];
                String registry = (String)fontDesc["Registry"];
                uniMap = "";
                foreach (String name in registryNames[registry + "_Uni"].Keys) {
                    uniMap = name;
                    if (name.EndsWith("V") && vertical)
                        break;
                    if (!name.EndsWith("V") && !vertical)
                        break;
                }
                if (cidDirect) {
                    cidUni = CMapCache.GetCachedCMapCidUni(uniMap);
                }
                else {
                    uniCid = CMapCache.GetCachedCMapUniCid(uniMap);
                    cidByte = CMapCache.GetCachedCMapCidByte(CMap);
                }
            }
            catch (Exception ex) {
                throw new DocumentException(ex.Message);
            }
        }
        
        /**
         * Returns a font compatible with a CJK encoding or null if not found.
         * @param enc
         * @return 
         */
        public static String GetCompatibleFont(String enc) {
            LoadProperties();
            String registry = null;
            foreach (KeyValuePair<String, Dictionary<String, object>> e in registryNames) {
                if (e.Value.ContainsKey(enc)) {
                    registry = e.Key;
                    foreach (KeyValuePair<String, Dictionary<String, Object>> e1 in allFonts) {
                        if (registry.Equals(e1.Value["Registry"]))
                            return e1.Key;
                    }
                }
            }
            return null;
        }
        
        /** Checks if its a valid CJK font.
         * @param fontName the font name
         * @param enc the encoding
         * @return <CODE>true</CODE> if it is CJK font
         */
        public static bool IsCJKFont(string fontName, string enc) {
            LoadProperties();
            if (!registryNames.ContainsKey("fonts"))
                return false;
            if (!registryNames["fonts"].ContainsKey(fontName))
                return false;
            if (enc.Equals(IDENTITY_H) || enc.Equals(IDENTITY_V))
                return true;
            String registry = allFonts[fontName]["Registry"] as string;
            Dictionary<String,object> encodings;
            registryNames.TryGetValue(registry, out encodings);
            return encodings != null && encodings.ContainsKey(enc);
        }
            
        /**
         * Gets the width of a <CODE>char</CODE> in normalized 1000 units.
         * @param char1 the unicode <CODE>char</CODE> to get the width of
         * @return the width in normalized 1000 units
         */
        public override int GetWidth(int char1) {
            int c = (int)char1;
            if (!cidDirect)
                c = uniCid.Lookup(char1);
            int v;
            if (vertical)
                v = vMetrics[c];
            else
                v = hMetrics[c];
            if (v > 0)
                return v;
            else
                return 1000;
        }
        
        public override int GetWidth(string text) {
            int total = 0;
            if (cidDirect) {
                foreach (char c in text) {
                    total += GetWidth(c);
                }
            }
            else {
                for (int k = 0; k < text.Length; ++k) {
                    int val;
                    if (Utilities.IsSurrogatePair(text, k)) {
                        val = Utilities.ConvertToUtf32(text, k);
                        k++;
                    }
                    else {
                        val = text[k];
                    }
                    total += GetWidth(val);
                }
            }
            return total;
        }
        
        internal override int GetRawWidth(int c, string name) {
            return 0;
        }
        public override int GetKerning(int char1, int char2) {
            return 0;
        }

        private PdfDictionary GetFontDescriptor() {
            PdfDictionary dic = new PdfDictionary(PdfName.FONTDESCRIPTOR);
            dic.Put(PdfName.ASCENT, new PdfLiteral((String)fontDesc["Ascent"]));
            dic.Put(PdfName.CAPHEIGHT, new PdfLiteral((String)fontDesc["CapHeight"]));
            dic.Put(PdfName.DESCENT, new PdfLiteral((String)fontDesc["Descent"]));
            dic.Put(PdfName.FLAGS, new PdfLiteral((String)fontDesc["Flags"]));
            dic.Put(PdfName.FONTBBOX, new PdfLiteral((String)fontDesc["FontBBox"]));
            dic.Put(PdfName.FONTNAME, new PdfName(fontName + style));
            dic.Put(PdfName.ITALICANGLE, new PdfLiteral((String)fontDesc["ItalicAngle"]));
            dic.Put(PdfName.STEMV, new PdfLiteral((String)fontDesc["StemV"]));
            PdfDictionary pdic = new PdfDictionary();
            pdic.Put(PdfName.PANOSE, new PdfString((String)fontDesc["Panose"], null));
            dic.Put(PdfName.STYLE, pdic);
            return dic;
        }
        
        private PdfDictionary GetCIDFont(PdfIndirectReference fontDescriptor, IntHashtable cjkTag) {
            PdfDictionary dic = new PdfDictionary(PdfName.FONT);
            dic.Put(PdfName.SUBTYPE, PdfName.CIDFONTTYPE0);
            dic.Put(PdfName.BASEFONT, new PdfName(fontName + style));
            dic.Put(PdfName.FONTDESCRIPTOR, fontDescriptor);
            int[] keys = cjkTag.ToOrderedKeys();
            string w = ConvertToHCIDMetrics(keys, hMetrics);
            if (w != null)
                dic.Put(PdfName.W, new PdfLiteral(w));
            if (vertical) {
                w = ConvertToVCIDMetrics(keys, vMetrics, hMetrics);
                if (w != null)
                    dic.Put(PdfName.W2, new PdfLiteral(w));
            }
            else
                dic.Put(PdfName.DW, new PdfNumber(1000));
            PdfDictionary cdic = new PdfDictionary();
            if (cidDirect) {
                cdic.Put(PdfName.REGISTRY, new PdfString(cidUni.Registry, null));
                cdic.Put(PdfName.ORDERING, new PdfString(cidUni.Ordering, null));
                cdic.Put(PdfName.SUPPLEMENT, new PdfNumber(cidUni.Supplement));
            }
            else {
                cdic.Put(PdfName.REGISTRY, new PdfString(cidByte.Registry, null));
                cdic.Put(PdfName.ORDERING, new PdfString(cidByte.Ordering, null));
                cdic.Put(PdfName.SUPPLEMENT, new PdfNumber(cidByte.Supplement));
            }
            dic.Put(PdfName.CIDSYSTEMINFO, cdic);
            return dic;
        }
        
        private PdfDictionary GetFontBaseType(PdfIndirectReference CIDFont) {
            PdfDictionary dic = new PdfDictionary(PdfName.FONT);
            dic.Put(PdfName.SUBTYPE, PdfName.TYPE0);
            string name = fontName;
            if (style.Length > 0)
                name += "-" + style.Substring(1);
            name += "-" + CMap;
            dic.Put(PdfName.BASEFONT, new PdfName(name));
            dic.Put(PdfName.ENCODING, new PdfName(CMap));
            dic.Put(PdfName.DESCENDANTFONTS, new PdfArray(CIDFont));
            return dic;
        }
        
        internal override void WriteFont(PdfWriter writer, PdfIndirectReference piref, Object[] parms) {
            IntHashtable cjkTag = (IntHashtable)parms[0];
            PdfIndirectReference ind_font = null;
            PdfObject pobj = null;
            PdfIndirectObject obj = null;
            pobj = GetFontDescriptor();
            if (pobj != null){
                obj = writer.AddToBody(pobj);
                ind_font = obj.IndirectReference;
            }
            pobj = GetCIDFont(ind_font, cjkTag);
            if (pobj != null){
                obj = writer.AddToBody(pobj);
                ind_font = obj.IndirectReference;
            }
            pobj = GetFontBaseType(ind_font);
            writer.AddToBody(pobj, piref);
        }
        
        /**
         * You can't get the FontStream of a CJK font (CJK fonts are never embedded),
         * so this method always returns null.
         * @return  null
         * @since   2.1.3
         */
        public override PdfStream GetFullFontStream() {
            return null;
        }

        private float GetDescNumber(string name) {
            return int.Parse((string)fontDesc[name]);
        }
        
        private float GetBBox(int idx) {
            string s = (string)fontDesc["FontBBox"];
            StringTokenizer tk = new StringTokenizer(s, " []\r\n\t\f");
            string ret = tk.NextToken();
            for (int k = 0; k < idx; ++k)
                ret = tk.NextToken();
            return int.Parse(ret);
        }
        
        /** Gets the font parameter identified by <CODE>key</CODE>. Valid values
         * for <CODE>key</CODE> are <CODE>ASCENT</CODE>, <CODE>CAPHEIGHT</CODE>, <CODE>DESCENT</CODE>
         * and <CODE>ITALICANGLE</CODE>.
         * @param key the parameter to be extracted
         * @param fontSize the font size in points
         * @return the parameter in points
         */
        public override float GetFontDescriptor(int key, float fontSize) {
            switch (key) {
                case AWT_ASCENT:
                case ASCENT:
                    return GetDescNumber("Ascent") * fontSize / 1000;
                case CAPHEIGHT:
                    return GetDescNumber("CapHeight") * fontSize / 1000;
                case AWT_DESCENT:
                case DESCENT:
                    return GetDescNumber("Descent") * fontSize / 1000;
                case ITALICANGLE:
                    return GetDescNumber("ItalicAngle");
                case BBOXLLX:
                    return fontSize * GetBBox(0) / 1000;
                case BBOXLLY:
                    return fontSize * GetBBox(1) / 1000;
                case BBOXURX:
                    return fontSize * GetBBox(2) / 1000;
                case BBOXURY:
                    return fontSize * GetBBox(3) / 1000;
                case AWT_LEADING:
                    return 0;
                case AWT_MAXADVANCE:
                    return fontSize * (GetBBox(2) - GetBBox(0)) / 1000;
            }
            return 0;
        }
        
        public override string PostscriptFontName {
            get {
                return fontName;
            }
            set {
                fontName = value;
            }
        }
        
        /** Gets the full name of the font. If it is a True Type font
         * each array element will have {Platform ID, Platform Encoding ID,
         * Language ID, font name}. The interpretation of this values can be
         * found in the Open Type specification, chapter 2, in the 'name' table.<br>
         * For the other fonts the array has a single element with {"", "", "",
         * font name}.
         * @return the full name of the font
         */
        public override string[][] FullFontName {
            get {
                return new string[][]{new string[] {"", "", "", fontName}};
            }
        }
        
        /** Gets all the entries of the names-table. If it is a True Type font
         * each array element will have {Name ID, Platform ID, Platform Encoding ID,
         * Language ID, font name}. The interpretation of this values can be
         * found in the Open Type specification, chapter 2, in the 'name' table.<br>
         * For the other fonts the array has a single element with {"4", "", "", "",
         * font name}.
         * @return the full name of the font
         */
        public override string[][] AllNameEntries {
            get {
                return new string[][]{new string[]{"4", "", "", "", fontName}};
            }
        }

        /** Gets the family name of the font. If it is a True Type font
         * each array element will have {Platform ID, Platform Encoding ID,
         * Language ID, font name}. The interpretation of this values can be
         * found in the Open Type specification, chapter 2, in the 'name' table.<br>
         * For the other fonts the array has a single element with {"", "", "",
         * font name}.
         * @return the family name of the font
         */
        public override string[][] FamilyFontName {
            get {
                return this.FullFontName;
            }
        }
        
        internal static IntHashtable CreateMetric(string s) {
            IntHashtable h = new IntHashtable();
            StringTokenizer tk = new StringTokenizer(s);
            while (tk.HasMoreTokens()) {
                int n1 = int.Parse(tk.NextToken());
                h[n1] = int.Parse(tk.NextToken());
            }
            return h;
        }
        
        internal static string ConvertToHCIDMetrics(int[] keys, IntHashtable h) {
            if (keys.Length == 0)
                return null;
            int lastCid = 0;
            int lastValue = 0;
            int start;
            for (start = 0; start < keys.Length; ++start) {
                lastCid = keys[start];
                lastValue = h[lastCid];
                if (lastValue != 0) {
                    ++start;
                    break;
                }
            }
            if (lastValue == 0)
                return null;
            StringBuilder buf = new StringBuilder();
            buf.Append('[');
            buf.Append(lastCid);
            int state = FIRST;
            for (int k = start; k < keys.Length; ++k) {
                int cid = keys[k];
                int value = h[cid];
                if (value == 0)
                    continue;
                switch (state) {
                    case FIRST: {
                        if (cid == lastCid + 1 && value == lastValue) {
                            state = SERIAL;
                        }
                        else if (cid == lastCid + 1) {
                            state = BRACKET;
                            buf.Append('[').Append(lastValue);
                        }
                        else {
                            buf.Append('[').Append(lastValue).Append(']').Append(cid);
                        }
                        break;
                    }
                    case BRACKET: {
                        if (cid == lastCid + 1 && value == lastValue) {
                            state = SERIAL;
                            buf.Append(']').Append(lastCid);
                        }
                        else if (cid == lastCid + 1) {
                            buf.Append(' ').Append(lastValue);
                        }
                        else {
                            state = FIRST;
                            buf.Append(' ').Append(lastValue).Append(']').Append(cid);
                        }
                        break;
                    }
                    case SERIAL: {
                        if (cid != lastCid + 1 || value != lastValue) {
                            buf.Append(' ').Append(lastCid).Append(' ').Append(lastValue).Append(' ').Append(cid);
                            state = FIRST;
                        }
                        break;
                    }
                }
                lastValue = value;
                lastCid = cid;
            }
            switch (state) {
                case FIRST: {
                    buf.Append('[').Append(lastValue).Append("]]");
                    break;
                }
                case BRACKET: {
                    buf.Append(' ').Append(lastValue).Append("]]");
                    break;
                }
                case SERIAL: {
                    buf.Append(' ').Append(lastCid).Append(' ').Append(lastValue).Append(']');
                    break;
                }
            }
            return buf.ToString();
        }
        
        internal static string ConvertToVCIDMetrics(int[] keys, IntHashtable v, IntHashtable h) {
            if (keys.Length == 0)
                return null;
            int lastCid = 0;
            int lastValue = 0;
            int lastHValue = 0;
            int start;
            for (start = 0; start < keys.Length; ++start) {
                lastCid = keys[start];
                lastValue = v[lastCid];
                if (lastValue != 0) {
                    ++start;
                    break;
                }
                else
                    lastHValue = h[lastCid];
            }
            if (lastValue == 0)
                return null;
            if (lastHValue == 0)
                lastHValue = 1000;
            StringBuilder buf = new StringBuilder();
            buf.Append('[');
            buf.Append(lastCid);
            int state = FIRST;
            for (int k = start; k < keys.Length; ++k) {
                int cid = keys[k];
                int value = v[cid];
                if (value == 0)
                    continue;
                int hValue = h[lastCid];
                if (hValue == 0)
                    hValue = 1000;
                switch (state) {
                    case FIRST: {
                        if (cid == lastCid + 1 && value == lastValue && hValue == lastHValue) {
                            state = SERIAL;
                        }
                        else {
                            buf.Append(' ').Append(lastCid).Append(' ').Append(-lastValue).Append(' ').Append(lastHValue / 2).Append(' ').Append(V1Y).Append(' ').Append(cid);
                        }
                        break;
                    }
                    case SERIAL: {
                        if (cid != lastCid + 1 || value != lastValue || hValue != lastHValue) {
                            buf.Append(' ').Append(lastCid).Append(' ').Append(-lastValue).Append(' ').Append(lastHValue / 2).Append(' ').Append(V1Y).Append(' ').Append(cid);
                            state = FIRST;
                        }
                        break;
                    }
                }
                lastValue = value;
                lastCid = cid;
                lastHValue = hValue;
            }
            buf.Append(' ').Append(lastCid).Append(' ').Append(-lastValue).Append(' ').Append(lastHValue / 2).Append(' ').Append(V1Y).Append(" ]");
            return buf.ToString();
        }
        
        internal static Dictionary<String, Object> ReadFontProperties(String name) {
            name += ".properties";
            Stream isp = StreamUtil.GetResourceStream(RESOURCE_PATH_CMAP + name);
            Properties p = new Properties();
            p.Load(isp);
            isp.Close();
            IntHashtable W = CreateMetric(p["W"]);
            p.Remove("W");
            IntHashtable W2 = CreateMetric(p["W2"]);
            p.Remove("W2");
            Dictionary<String, Object> map = new Dictionary<string,object>();
            foreach (string key in p.Keys) {
                map[key] = p[key];
            }
            map["W"] = W;
            map["W2"] = W2;
            return map;
        }

        public override int GetUnicodeEquivalent(int c) {
            if (cidDirect) {
                if (c == CID_NEWLINE)
                    return '\n';
                return cidUni.Lookup(c);
            }
            return c;
        }
        
        public override int GetCidCode(int c) {
            if (cidDirect)
                return c;
            return uniCid.Lookup(c);
        }

        public override bool HasKernPairs() {
            return false;
        }

        public override bool CharExists(int c) {
            if (cidDirect)
                return true;
            return cidByte.Lookup(uniCid.Lookup(c)).Length > 0;
        }

        public override bool SetCharAdvance(int c, int advance) {
            return false;
        }

        public override bool SetKerning(int char1, int char2, int kern) {
            return false;
        }

        public override int[] GetCharBBox(int c) {
            return null;
        }

        protected override int[] GetRawCharBBox(int c, String name) {
            return null;
        }
        /**
         * Converts a <CODE>String</CODE> to a </CODE>byte</CODE> array according
         * to the font's encoding.
         * @param text the <CODE>String</CODE> to be converted
         * @return an array of <CODE>byte</CODE> representing the conversion according to the font's encoding
         */
        public override byte[] ConvertToBytes(String text) {
            if (cidDirect)
                return base.ConvertToBytes(text);
            if (text.Length == 1)
                return ConvertToBytes((int)text[0]);
            MemoryStream bout = new MemoryStream();
            for (int k = 0; k < text.Length; ++k) {
                int val;
                if (Utilities.IsSurrogatePair(text, k)) {
                    val = Utilities.ConvertToUtf32(text, k);
                    k++;
                }
                else {
                    val = text[k];
                }
                byte[] b = ConvertToBytes(val);
                bout.Write(b, 0, b.Length);
            }
            return bout.ToArray();
        }
        
        /**
         * Converts a <CODE>char</CODE> to a </CODE>byte</CODE> array according
         * to the font's encoding.
         * @param char1 the <CODE>char</CODE> to be converted
         * @return an array of <CODE>byte</CODE> representing the conversion according to the font's encoding
         */
        internal override byte[] ConvertToBytes(int char1) {
            if (cidDirect)
                return base.ConvertToBytes(char1);
            return cidByte.Lookup(uniCid.Lookup(char1));
        }
        
        virtual public bool IsIdentity() {
            return cidDirect;
        }
    }
}
